Page 12
D00073611 Siemens SD 270 Service Manual
Present Time:
Select the minimum and maximum times that a stimulus
can sound when the PRESENT key is pressed; either 0.5sec
(min) & 10sec (max); or 1.0 sec (min) & 2.0 sec (max)
FF Speech units:
The units for freefield speech may be switched
between dBHL and dBSPL
3.6.3
Description of Function of Other Keys
SIGNAL
The rotary control is used to increase or decrease the
signal level in the selected step size.
MASK
The rotary control is used to increase or decrease the
masking level in the selected step size. (The MASK key
must be selected)
SINE
Selects a pure tone as the test signal; the indicator above
the key illuminates green
WARBLE
Selects a frequency modulated tone as the test signal; the
indicator above the key illuminates green
SPEECH
Selects speech mode; the indicator above the key
illuminates green; refer to Appendix 1 for details (note that
initially, only Softkeys 1 & 3 have a function)
MASK
Switches on masking at 30dBHL - narrow band (for pure
tones) or speech-weighted masking; the indicators above
the key and to the right of the display illuminate green; for
speech mode use Softkey 4 to select INT for internally
generated noise or EXT (with Softkey 1 used to select
LINE) to route recorded noise via the Line In connection
LEFT
Press once to select the left ear; the indicator above the
key illuminates green
RIGHT
Press once to select the right ear; the indicator above the
key illuminates green
PULSE
Enables pulse tone present function; the indicator above
the key illuminates green